Fusible link



Feb. 10, 1942. p vomcH 2,272,857

FUSIBLE LINK Filed Sept. 27, 1940 INVENTOR Pezer G. Z/onich Patented Feb. 10, 1942 .2 Claims.

This invention relates generally to an improvement in automatic sprinkler systems for fire protection, and in particular the invention is directed to an improvement in the construction of the sprinkler heads, together with the system of actuating the same.

The principal object of the invention is to provide a sprinkler head arranged to open upon the heat of a fire reaching the same, or to be opened by means of an electric circuit including 1 a switch disposed at a remote point.

Another object of the invention is to provicle a valve sprinkler head which includes a fusible linl normally maintaining the head valve clcsed; said link being adapted to fuse and release or allow the valve to open due to the heat of a fire, or by heat caused by the resistance to an electric current passed through said link.

A further object of the invention is to produce a simple and inexpensive device and yet one which will be exceedingly effectiv for the purpose for which it is designecl.

These objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawing similar eharacters of reference indicate corresponding parts in the several views:

Figure 1 is an elevation of the improved sprinkler head.

Figure 2 is a section taken on line 22 of Fig. 1 and including a diagrammatic showing of the electrical remote control circuit.

Referring now more particularly to the characters of reference on the drawing, the improved sprinkler head comprises an upstanding hollow body l threaded as at 2 for mounting in connection with a water supply pipe. At its upper end the body is formed with a port 3 surrounded by a valve seat 4; an axially movable dise valve 5 lncluding a sealing washer G normally being engaged with valve seat 4 or in closed position. This dise valve 5 tends to open under the normal water pressure in body I, but is releasably held in closed position by the mechanism hereinafter described.

The body is formed with an integral, upstanding yoke 7 which at its lower ends terminates on opposite sides of the body and is elongated so that its upper end is clisposed a substantial distance above dise valve 5. A vertical adjustment screw 8 is threacled through the upper end of yoke 1, and exteriorly of the latter is formed with a finger engaging head 9.

The lovver;end of adjustmentscrew :3sand the top of discvalve 5 are fo1mecl -withtapered recesses m and il respectively. A.pair of toggle or snap action levers 12 are clisposed between said screw and valve in.end .to.end.engagement and are formed at oppositezends with cone points 13 which engageinrecesses [0 and H respectively, formingneedle bearings. Also,4atadjacent ends, levers [2 are formed with a needle bearing l4.

Arms [5 are formed integral with and project laterally from both levers l2; such arms at their outer ends being formed with oppositely facing hooks I5. A fusible link I1 having spaced orifices 0 therein extends between such hooks; the hooks engaging in said orifices. The uppermost one of said orifices is fitted with an insulation ring or collar Il; for the purpose hereinafter set forth.

When hooks i6 are engaged in the spaced orifices in link H, and the adjustment screw 8 is run clown into firm contact with the adjacent lever 12 and to place said levers under compression, said levers are 01 dead center in the direction of link Il. Such link is of metal fusible at a predetermined temperature whereby it will melt due to the heat of the adjacent fire, or will melt by the heat of resistance as an electrc current is passed therethrough. The metal from which link 17 is constructed is of a type having considerable resistance to a current.

A lead Wire l9 xtends from the end of the link adjacent the orifice fitted with the insulation ring 13 to one of a pair of current supply wires 26. Another lead wire 2l extends from the other of said current supply Wires to the body of the sprinkler head; a normally open switch 22 being interposed in wire 2l.

In use, the above described sprinkler head is mounted in the conventional manner on a water supply pipe, not shown. These heads may be wired individually, or in banks having a single control switch therefor. If a fire occurs and the heat therefrom strikes link il, such link will melt, permitting arms 15 to fly apart under the influence of upwardly urged dise valve 5, and offcenter toggle levers l2, whereupon such valve opens and the water flows therefrom. However, if the sprinkler head is not sufilciently close to the fire to open by heat therefrom, the sprinkler head may be opened by closing switch 22. This causes a, current to fiow through wire l 9, nm: l 1, the lowermost one of arms i5, body I and through Wire 21. The resistance of link il to the current immediately creates substantial heat,

causing the link to melt and the sprinkler head to open in the manner previously described.

From the foregcing description it will be readi1y seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of of the invention, as defined by the appended claims.

Having thus described my invention, what I claim as new and useful and desire to secure by Letters Patent 1s:

1. In a sprinkler system, a sprinkler head including a body having a valve seat, a self-opening valve cooperating with said seat, a rigid yoke on the body extending over the valve and seat in spaced relation thereto, the valve opening toward the outer end of the yoke, a manual adjustment screw threaded through the outer end of the yoke in axial alinement with the valve, a toggle lever assembly extending between and engaging the adjacent ends of the valve and adjustment screw, and normally holding the valve closed, arms rigid With and projecting transversely in the same direction from the toggle levers, an electrcally fusible lin]; having spaced orifices therein, the outer end portions of said arms projecting through said orifices whereby the link normally prevents separating movement of the arms and resultant togsle action of said assembly, means insulating the link from one of the arms, and a normally open current supply circuit having one wire thereof direct connected with the link, the other side of the circuit being grounded in relation to the sprinkler head; said arms being urged apart, and the other arm urged into positive electrical contact With the link, by the compression applied to the toggle lever assembly by said valve and adjustment screw.

2. In a sprinkler system which includes a sprinkler head having a normally closed but releasable valve and a pair of spaced arms separable to release the valve; an electrica1ly fusible link having spaced orifices therethrough, the arms projecting through said orifices and the link normally preventing separation of said arms, means insulating the link from one of the arms, and a normally open current supply circuit including one wire connected with the link at a point remote from the other arm and corresponding orifice, the other side of the circuit be ing in grounded relation to said 0ther arm.

PETER G. VONICH. 

